#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <unistd.h>
#include <unistd.h>
#include <unistd.h>

//验证0,1,2就是标准IO
int main()
{
    const char* str = "Hello World!\n";

    write(1, str, strlen(str));
    write(2, str, strlen(str));
    return 0;
}
